A sling of this type is known under the term "cinching". It is constituted by a metal wire, particularly of steel, of which the two ends are definitively fixed to each other; this wire forms a figure-of-eight of which the loops are folded down on each other and joined together, on their common part, by sliding sleeves; the smaller loop is intended to surround the package and to self-cinch thereon when the larger, so-called lifting loop is suspended from a hook, and said package, by weighing thereon, tends to lengthen it by narrowing the smaller, so-called cinching loop.
This sling presents the drawback of consuming substantially double the amount of metal wire of an ordinary endless sling disposed normally, i.e. without a "round turn" around the package. However, its advantages are multiple: it ensures connection of the elements composing the load and avoids slidings of said load, whether it be unitary or composite.
When it is desired to increase the lifting force, the number of slings suspended from the same hook is multiplied and, consequently, as many cinching loops as lifting loops are employed. The drawback of this arrangement is that the consumption of metal wire is excessive and expensive.
It is an object of the present invention to overcome this drawback by proposing a single sling which conserves all the advantages of the multiple slings mentioned hereinbefore, namely self-cinching on the package, facility of placing and removing the sling, increase in the lifting force.